Awww! That's a bummer to hear about!
Any pony can be restored, I think.
Somebody with the proper sculpting talents could fill in the puncture marks and reconstruct the pieces that are missing.
Depending on how you'd like the restoration to be handled, I'd wager that some re-painting might be necessary as well. Somebody with a good eye for color and an airbrush might be able to spot-paint it, but realistically, you might be looking at a full repaint.
There are a whole lot of talented people on the Arena. I bet if you posted pictures, the custom artists here could weigh in with their thoughts!